First-floor extensions in Brierley Hill

Brierley Hill: the key facts for this kind of project.

Postcode districts: DY5
County / area: West Midlands, England
Price region: West Midlands
Guide price: £25,000–£36,500 (£1,800–£2,600 per m²)
Approval route: It may be permitted development if it goes no more than 3 m beyond the original rear wall (counting any single-storey part) and stays 7 m from the rear boundary; otherwise it needs planning permission.
Nearest towns: Stourbridge (2 miles), Dudley (2 miles), Kingswinford (2.3 miles)
Distance to Birmingham: about 9.3 miles
First visit: Free, no obligation

About a first-floor extension

A first-floor extension suits you if your house already has a single-storey extension and you need more space upstairs. You get a structural check of the existing walls and foundations, a design that ties the new floor into the house, the approvals your nation needs, building regulations approval and the build, managed by us and carried out by vetted teams working under S&K.

Around Brierley Hill we also work in Stourbridge, Dudley and Kingswinford, and across the rest of the West Midlands. Postcode district in and near Brierley Hill: DY5.

What it costs in Brierley Hill

Using our West Midlands rates, a first-floor extension with 4 m × 3.5 m of new first-floor space (14 m²) comes to about £25,000–£36,500, including VAT. Bigger or more glazed designs cost more per m². Design fees, structural calculations and approval fees are separate and listed on our prices page.

Spec	Per m²	4 m × 3.5 m of new first-floor space (14 m²)
Essential	£1,660–£2,390 per m²	£23,000–£33,500
Standard	£1,800–£2,600 per m²	£25,000–£36,500
Premium	£2,160–£3,120 per m²	£30,000–£43,500

Planning and building regulations in Brierley Hill

In England, adding a first floor turns a single-storey extension into one of more than one storey. To be permitted development, the extension as a whole must go no more than 3 m beyond the rear wall of the original house and stay at least 7 m from the rear boundary, with matching materials and roof pitch. Over a side extension it always needs planning permission, costing £548 (or £575 for applications made from 8 December 2026).

Approval in England: Householder planning application: £548 (or £575 for applications made from 8 December 2026). Lawful development certificate: £274 (about £288 for applications from 8 December 2026). Councils should decide householder applications within 8 weeks of validation.

Building regulations: Building regulations approval (full plans recommended) from the council or a registered building control approver, with a completion certificate at the end.

Design points for Brierley Hill homes

Escape and fire safety

A new first-floor bedroom needs an escape window with a clear opening of at least 0.33 m², at least 450 mm wide and 450 mm high, with the bottom no more than 1,100 mm above the floor, unless there is a protected route to the stairs.

Can the existing structure take it?

Many single-storey extensions were built with foundations, walls and lintels sized for one storey. We find out what is there with trial holes and, where available, the original building control drawings. The engineer then decides whether to reuse, strengthen or rebuild parts of the structure.

How we'd run your project

Look at the house
We start in Brierley Hill with a free visit: measurements, photos, a look at the loft and drains, and a frank chat about budget.
Design and approvals
We draw the extension and check it against the rules for England, then apply for planning permission or a certificate of lawfulness, whichever fits.
Price it properly
Once the engineer's calculations are in, we fix the build price in writing, with a clear list of what's included.
Finish and certify
Second fix, plastering and making good, then building control's final inspection and the completion paperwork.

Questions about first-floor extensions in Brierley Hill

Which postcodes do you cover around Brierley Hill?

We cover Brierley Hill (DY5) and nearby places including Stourbridge, Dudley and Kingswinford, plus the rest of the West Midlands. The first site visit is free.

How much does a first-floor extension cost in Brierley Hill?

Our guide for the West Midlands, which covers Brierley Hill, is £1,800–£2,600 per m² including VAT. A typical project with 4 m × 3.5 m of new first-floor space (14 m²) comes to about £25,000–£36,500. Design and approval fees are extra, and we fix the build price in writing once the design is agreed.

Do I need planning permission for a first-floor extension in Brierley Hill?

Brierley Hill is in England, so England planning rules apply. It may be permitted development if it goes no more than 3 m beyond the original rear wall (counting any single-storey part) and stays 7 m from the rear boundary; otherwise it needs planning permission. If in doubt, a lawful development certificate or a planning application gives you certainty before you build.

What happens to the room below while the first floor is built?

The old roof is removed, so the room below is exposed for a short period. We fit temporary weather protection, plan the work so the roof comes off only when the new structure is ready, and agree with you which rooms will be out of use and for roughly how long.

Will the first-floor extension match my house?

It should, and in England matching materials and roof pitch is a condition of permitted development. We match brick, tile, mortar colour and window style where we can, and tell you at the design stage if an exact brick match is not available, so you can choose between the closest match and render or cladding.

Nearby

The same service in neighbouring towns:

Other extensions in Brierley Hill

All two-storey extension services in Brierley Hill · First-floor extensions across the West Midlands

Send us your postcode and a few details. We'll get back to you to arrange a visit and talk through your options.